The mean stature of the long-leaved pine is sixty or seventy feet, with a uniform diameter of fifteen or sixteen inches for two thirds of this height. Some stocks, favored by local circumstances, attain much larger dimensions, particularly in East Florida. The timber is very valuable, being stronger, more compact, and more durable, than that of all the other species of pine: it is besides fine grained, and susceptible of high polish. Its uses are diversified, and its consumption great. But the value of the long-leaved pine does not reside exclusively in its wood; it supplies nearly all the resinous matter used in the United States in ship-building, with a large residue for exportation; and in this view, its place can be supplied by no other species, those which afford the same product being dispersed through the woods, or collected in inaccessible places. In the northern states, the lands, which at the commencement of their settlements were covered with pitch pine, were exhausted in twenty-five or thirty years, and for more than half a century have ceased to furnish tar. The pine-barrens are of vast extent, and are covered with trees of the forest growth; but they cannot all be rendered profitable, from the difficulty of communicating with the sea. Among the varieties which we can only enumerate, without an attempt at description, are the _New Jersey_, _Table Mountain_, _Gray_, _Pond_, and _White Pine_. _Spruces._――The _American Silver Fir_ is found in the colder regions of the states; towards the south, it is found only on the tops of the Alleghanies. It flourishes best in a moist, sandy loam. Its height rarely exceeds forty feet, with a diameter of twelve or fifteen inches. The trunk tapers from a foot in diameter at the surface of the ground to seven or eight inches at the height of six feet. When standing alone and developing itself naturally, its branches, which are numerous and thickly garnished with leaves, diminish in length in proportion to their height, and form a pyramid of perfect regularity. The bark is smooth and delicate. The leaves are six or eight lines long, and are inserted singly on the sides and on the top of the branches; they are narrow, rigid and flat, of a bright green above, and a silvery white beneath; whence probably is derived the name of the tree. The flowers appear in May, and are followed by cones of a fragrant odor, nearly cylindrical, four or five inches long, an inch in diameter, and always directed upwards. The seeds are ripe in autumn, and if permitted to hang late will fall apart and scatter themselves. The wood of the silver fir is light and slightly resinous, and the heart is yellowish.